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    <title>Document</title>
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<body>
    <script>
        var arr = [true,true,false,true]
        Array.prototype.myEvery= function(fn){
            var flag = true;
            for(var i=0;i<this.length;i++){
                var res = fn(this[i],i,this);
                flag = flag && res;
                if(!flag){
                    break;
                }
            }
            return flag;
        }
        var res = arr.myEvery(function(item){
            console.log(item);
            return item;
        })
        console.log(res);
    </script>
    
</body>
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